A two-member committee appointed by the National Green Tribunal (NGT) has directed the Delhi government to set up an early warning system for the Yamuna, which can alert authorities when the level of ammonia in the river water crosses the safe limits during the winter months.

The Delhi Pollution Control Committee (DPCC) has been directed to submit a timeline by which the system could be set up. HT has a copy of the letter sent to the authorities on Monday.

“On August 29, 2018, the monitoring committee in its meeting with the Central Pollution Control Board (CPCB), Delhi Pollution Control Committee and Delhi Jal Board, recognizing the recurrent problem of rise in ammonia levels in Yamuna, had directed that an online monitoring system should be installed for monitoring levels of pollution in Yamuna at Palla and Wazirabad. Installation of an online monitoring system would have immediately given advance warning to the DJB and others to take corrective measures. Regrettably, the monitoring committee has received no feedback from DPCC on this,” the letter issued by the committee on Monday stated.

This comes at a time when the DJB had to shut down three water treatment plants (WTPs) on Sunday after concentration of ammonia in the river water shot up at least two times above the limit that could be treated by the treatment plants.

“Why despite the monitoring committee’s decision, an online system for ammonia monitoring has not been installed at Palla and Wazirabad. The DPCC should also submit a timeline by which such system will be installed,” the letter, signed by Shailaja Chandra and BS Sajwan, members of the NGT-appointed committee, stated. While Chandra is the former chief secretary of Delhi, Sajwan is a former expert member of the NGT.

Meanwhile, the concentration of ammonia in the river water dropped from 1.8 ppm on Sunday to 0.2 ppm on Monday. DJB water treatment plants can handle up to 0.9 ppm of ammonia in the water. The plants need to be shut down if the level exceeds 0.9 ppm resulting in water crisis in several parts of the city.

“Situation is normal now. All the three WTPs, which had to be shut down on Sunday, are now working. We are already monitoring the water quality at Wazirabad and Palla to check water pollution,” said Dinesh Mohaniya, vice- chairman of DJB.

A team comprising representatives from CPCB and National Environmental Engineering Research Institute (NEERI) has been directed to find out the sources of ammonia and file a report.

The committee has also directed the CPCB to confirm whether all polluting industries and sewage treatment plants (STPs) in Haryana are connected to the CPCB’s server for online monitoring.

In February 2018, the NGT had directed the chief secretaries of two states – Delhi and Haryana -- to come up with a road map so that the recurrent issue of spike in ammonia levels in the river every winter could be resolved. On Monday, the NGT-appointed committee directed the chief secretaries of the two states to find out why the problem has cropped up again and take corrective measures. They have also been asked to come up with a standard operating procedure.

Spike in ammonia levels is a recurrent problem, which takes place every winter, and ends up in a blame game between Delhi and Haryana. Every time there is a spike in ammonia levels in the Yamuna, Delhi alleges that Haryana-based industries were dumping waste into the river. Haryana says that drop in water level during winter aggravates the problem, even though the state is supplying adequate water to Delhi.

The ministry of earth sciences has already set up an early warning system for Delhi to forecast air pollution at least 48 hours in advance. It was launched in October this year.

First Published: Dec 04, 2018 13:27 IST